yogi_Sum Values In column C For Specified Name In Column D And Specified Month In Column A

Yogi Anand, D.Eng, P.E.      Google Spreadsheet   Post  #772  Sep 22, 2012    www.energyefficientbuild.com. 

user moldow said: (http://productforums.google.com/forum/?zx=jsaua8jog7d0#!category-topic/docs/spreadsheets/TrC6NdsUs3k)
How function use?

Good Morning. I have question. My table look like this:

Month    |    Description    | Price   |  Person

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January  |  Some text here1  | 10,50€  |  John

January  |  Some text here2  |  3,60€  |  John 

January  |  Some text here3  | 40,89€  |  Bob 

February |  Some text here4  | 23,60€  |  John 

February |  Some text here5  | 30,78€  |  Bob 

February |  Some text here6  |  8,56€  |  Bob 

I need function, which do follows:

Select person John, where month is January and do sum(Price)

Some inspiration for me? Thank you very much.

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following is a solution to the problem